Detecting data in multiantenna wireless communication systems

ABSTRACT

A multiple-input multiple output (MIMO) wireless receiver is provided to detect data in MIMO streams received via a multi-antenna system. A filter based detector performs a first pass at decoding codewords in a MIMO bitstream, and then a parity check is performed to determine that the codewords were decoded correctly. If one or more codewords are decoded correctly, those codewords can be used as a candidate codeword and used to generate a bit log likelihood ratio as an input for a second MIMO detector pass which uses a list based MIMO detector. The first pass with a high speed, simple detector facilitates decreasing the list size for the second, optimum list based detector which helps improve overall throughput.

TECHNICAL FIELD

The disclosed subject matter relates to detecting data in multiantennawireless communications systems to enable improvement of wireless systemperformance over conventional wireless system technologies, e.g., forfifth generation (5G) technologies or other next generation networks.

BACKGROUND

To meet the huge demand for data centric applications, third generationpartnership project (3GPP) systems and systems that employ one or moreaspects of the specifications of fourth generation (4G) standards forwireless communications will be extended to fifth generation (5G)standards for wireless communications. Unique challenges exist toprovide levels of service associated with forthcoming 5G and/or othernext generation standards for wireless networks.

BRIEF DESCRIPTION OF THE DRAWINGS

Non-limiting and non-exhaustive embodiments of the subject disclosureare described with reference to the following figures, wherein likereference numerals refer to like parts throughout the various viewsunless otherwise specified.

FIG. 1 illustrates an example block diagram of a wireless communicationsystem that detects data in multiantenna transmission in accordance withvarious aspects and embodiments of the subject disclosure.

FIG. 2 illustrates an example block diagram of a multiple-input multipleoutput (MIMO) wireless receiver that facilitates detecting data inmulti-antenna wireless systems in accordance with various aspects andembodiments of the subject disclosure.

FIG. 3 illustrates an example block diagram of a MIMO bitstream that hastwo decoding passes performed in accordance with various aspects andembodiments of the subject disclosure.

FIG. 4 illustrates an example block diagram showing a MIMO wirelessreceiver device in accordance with various aspects and embodiments ofthe subject disclosure.

FIG. 5 illustrates an example table showing improvements to throughputusing the MIMO wireless receiver in accordance with various aspects andembodiments of the subject disclosure.

FIG. 6 illustrates an example graph showing improvements in linkthroughput using the MIMO wireless receiver in accordance with variousaspects and embodiments of the subject disclosure.

FIG. 7 illustrates an example method for detecting data in MIMO wirelessreceivers in accordance with various aspects and embodiments of thesubject disclosure.

FIG. 8 illustrates an example method for detecting data in MIMO wirelessreceivers in accordance with various aspects and embodiments of thesubject disclosure.

FIG. 9 illustrates an example block diagram of an example user equipmentoperable to provide an adaptive downlink control channel structure inaccordance with various aspects and embodiments of the subjectdisclosure.

FIG. 10 illustrates an example block diagram of a computer that can beoperable to execute processes and methods in accordance with variousaspects and embodiments of the subject disclosure.

DETAILED DESCRIPTION

One or more embodiments are now described with reference to thedrawings, wherein like reference numerals are used to refer to likeelements throughout. In the following description, for purposes ofexplanation, numerous specific details are set forth in order to providea thorough understanding of the various embodiments. It is evident,however, that the various embodiments can be practiced without thesespecific details (and without applying to any particular networkedenvironment or standard).

A multiple-input multiple output (MIMO) wireless receiver is provided todetect data in MIMO streams received via a multi-antenna system. Afilter based detector performs a first pass at decoding codewords in aMIMO bitstream, and then a parity check is performed to determine thatthe codewords were decoded correctly. If one or more codewords aredecoded correctly, those codewords can be used as a candidate codewordand used to generate a bit log likelihood ratio as an input for a secondMIMO detector pass which uses a list based MIMO detector. The first passwith a high speed, simple detector facilitates decreasing the list sizefor the second, optimum list based detector which helps improve overallthroughput.

To at least these and related ends, a system can comprise a processorand a memory that stores executable instructions that, when executed bythe processor, facilitate performance of operations, including receivinga bitstream comprising multiplexed codewords, wherein the bitstream issubject to an inter-stream interference. The operations can alsocomprise performing a first pass with respect to the bitstream to reducethe inter-stream interference using a first multiple-inputmultiple-output detector. The operations can also comprise in responseto performing the first pass, determining that a first codeword of themultiplexed codewords passed a parity check and a second codeword of themultiplexed codewords did not pass the parity check. The operations canalso comprise performing a second pass with respect to the bitstream tofurther reduce the inter-stream interference using a secondmultiple-input multiple-output detector different from the firstmultiple-input multiple-output detector, wherein an output of the firstpass is used as a input for the second pass.

In another embodiment, a method can comprise receiving, by a devicecomprising a processor, a bitstream comprising multiplexed codewords.The method can also comprise performing, by the device, a first decodingpass with a first multiple-input multiple-output detector. The methodcan also comprise determining, by the device, that a first codewordpasses a parity check and a second codeword does not pass the paritycheck. The method can also comprise performing, by the device, a seconddecoding pass with a second multiple-input multiple-output detector,wherein the first codeword of the first decoding pass is used as acandidate codeword for the second decoding pass.

In another embodiment, a machine-readable storage medium, comprisingexecutable instructions that, when executed by a processor of a device,facilitate performance of operations. The operations can comprisereceiving a signal from a multiple-input multiple-output antenna, thesignal comprising multiplexed codewords. The operations can alsocomprise performing a first decoding pass on the multiplexed codewordswith a first multiple-input multiple-output detector. The operations canalso comprise determining that a first codeword passes a parity checkand a second codeword does not pass the parity check. The operations canalso comprise generating a bit log-likelihood ratio from an output ofthe first decoding pass and performing a second decoding pass with asecond multiple-input multiple-output detector to decode the secondcodeword, wherein the bit log-likelihood ratio is used to facilitate thesecond decoding pass.

MIMO is an advanced antenna technique that improves the spectralefficiency of a transmission and thereby boosts the overall systemcapacity. The MIMO technique uses a commonly known notation (M×N) torepresent MIMO configuration in terms number of transmit (M) and receiveantennas (N). Multiple transmit and receive antennas can significantlyincrease the data carrying capacity of wireless systems, but MIMOdetector which identify and decode the multiplexed codewords haveseveral tradeoffs. There are a group of MIMO detectors that are simple,and easy to implement, but their bit error rate or frame error rateperformance is significantly inferior to that of an optimal MIMOdetector. This first group of MIMO detectors can be filter baseddetectors such as Linear detectors include zero-forcing (ZF) and minimummean-square error (MMSE) detectors, and the nonlinear receivers includedecision feedback, nulling-canceling and variants relying on successiveinterference cancelation.

Optimum, or near optimal detectors, such as list-based detectors,maximum likelihood detector, maximum a posteriori probability detector,(ML/MAP) sphere decoding detector, or list sphere decoding detector,have significantly better bit error rates and frame error rates, but thecomplexity of the detector increases exponentially with the number oftransmit antennas and/or the number of bits per constellation point.

In an embodiment, by first performing a decoding pass using one of thefilter based MIMO detectors, if one or more of the codewords of themultiplexed codewords bitstream is correctly decoded, then the list sizefor the list based MIMO detectors can be reduced, which allows thecodewords that were previously undetected, or improperly decoded afterthe first pass to be decoded properly during the second pass with thelist based detector. Since the list size has been reduced, thecomplexity of the second pass is also correspondingly reduced, andthroughput of the MIMO receiver can be improved. This technique can befaster than the traditional technique of sending negativeacknowledgements and receiving retransmissions.

Turning now to FIG. 1, illustrated is an example block diagram of awireless communication system 100 that detects data in multiantennatransmission in accordance with various aspects and embodiments of thesubject disclosure. In one or more embodiments, system 100 can compriseone or more user equipment UEs 104 and 102, which can have one or moreantenna panels having vertical and horizontal elements. A UE 102 can bea mobile device such as a cellular phone, a smartphone, a tabletcomputer, a wearable device, a virtual reality (VR) device, a heads-updisplay (HUD) device, a smart car, a machine-type communication (MTC)device, and the like. User equipment UE 102 can also comprise IOTdevices that communicate wirelessly. In various embodiments, system 100is or comprises a wireless communication network serviced by one or morewireless communication network providers. In example embodiments, a UE102 can be communicatively coupled to the wireless communication networkvia a network node or base station device 106.

The non-limiting term network node (or radio network node) is usedherein to refer to any type of network node serving a UE 102 and UE 104and/or connected to other network node, network element, or anothernetwork node from which the UE 102 or 104 can receive a radio signal.Network nodes can also have multiple antennas for performing varioustransmission operations (e.g., MIMO operations). A network node can havea cabinet and other protected enclosures, an antenna mast, and actualantennas. Network nodes can serve several cells, also called sectors,depending on the configuration and type of antenna. Examples of networknodes (e.g., network node 106) can comprise but are not limited to:NodeB devices, base station (BS) devices, access point (AP) devices, andradio access network (RAN) devices. The network node 106 can alsocomprise multi-standard radio (MSR) radio node devices, including butnot limited to: an MSR BS, an eNode B, a network controller, a radionetwork controller (RNC), a base station controller (BSC), a relay, adonor node controlling relay, a base transceiver station (BTS), atransmission point, a transmission node, an RRU, an RRH, nodes indistributed antenna system (DAS), and the like. In 5G terminology, thenode 106 can be referred to as a gNodeB device.

In example embodiments, the UE 102 and 104 can send and/or receivecommunication data via a wireless link to the network node 106. Thedashed arrow lines from the network node 106 to the UE 102 and 104represent downlink (DL) communications and the solid arrow lines fromthe UE 102 and 104 to the network nodes 106 represents an uplink (UL)communication.

Wireless communication system 100 can employ various cellulartechnologies and modulation schemes to facilitate wireless radiocommunications between devices (e.g., the UE 102 and 104 and the networknode 106). For example, system 100 can operate in accordance with aUMTS, long term evolution (LTE), high speed packet access (HSPA), codedivision multiple access (CDMA), time division multiple access (TDMA),frequency division multiple access (FDMA), multi-carrier code divisionmultiple access (MC-CDMA), single-carrier code division multiple access(SC-CDMA), single-carrier FDMA (SC-FDMA), OFDM, (DFT)-spread OFDM orSC-FDMA)), FBMC, ZT DFT-s-OFDM, GFDM, UFMC, UW DFT-Spread-OFDM, UW-OFDM,CP-OFDM, resource-block-filtered OFDM, and UFMC. However, variousfeatures and functionalities of system 100 are particularly describedwherein the devices (e.g., the UEs 102 and 104 and the network device106) of system 100 are configured to communicate wireless signals usingone or more multi carrier modulation schemes, wherein data symbols canbe transmitted simultaneously over multiple frequency subcarriers (e.g.,OFDM, CP-OFDM, DFT-spread OFMD, UFMC, FMBC, etc.).

In various embodiments, system 100 can be configured to provide andemploy 5G wireless networking features and functionalities. 5G wirelesscommunication networks are expected to fulfill the demand ofexponentially increasing data traffic and to allow people and machinesto enjoy gigabit data rates with virtually zero latency. Compared to 4G,5G supports more diverse traffic scenarios. For example, in addition tothe various types of data communication between conventional UEs (e.g.,phones, smartphones, tablets, PCs, televisions, Internet enabledtelevisions, etc.) supported by 4G networks, 5G networks can be employedto support data communication between smart cars in association withdriverless car environments, as well as machine type communications(MTCs). Considering the drastic different communication needs of thesedifferent traffic scenarios, the ability to dynamically configurewaveform parameters based on traffic scenarios while retaining thebenefits of multi carrier modulation schemes (e.g., OFDM and relatedschemes) can provide a significant contribution to the highspeed/capacity and low latency demands of 5G networks. With waveformsthat split the bandwidth into several sub-bands, different types ofservices can be accommodated in different sub-bands with the mostsuitable waveform and numerology, leading to an improved spectrumutilization for 5G networks.

In various embodiments, the network node 106 and UE 104 and 102 canemploy MIMO techniques to improve spectral efficiency of transmissionssent between the devices. MIMO can multiply the capacity of the radiolinks by using multiple transmit and receive antennas to exploitmultipath propagation. A multiantenna receiver on either one of the UEs102 or 104 or on the network node 106 can receive a transmission thatcomprises a bitstream comprising multiplexed codewords. A MIMO detectorcan be utilized to detect the codewords in the bitstream, and then adecoder can decode the codewords.

Please note that, although the disclosure generally refers to a MIMOsystem as a single user MIMO with multiple codewords. However thisinvention is equally applicable to multi user MIMO with single or moretransmit antennas. The invention is applicable to both downlink anduplink transmissions. The embodiments are described in particular foroperation of NR, E-UTRA/LTE/LTE-A, UTRA/HSPA FDD systems. Theembodiments are however applicable to any RAT or multi-RAT system wherethe UE operates using MIMO e.g. LTE TDD, GSM/GERAN, Wi Fi, WLAN, WiMax,CDMA2000, LTE-NX, Massive MIMO systems etc.

In an embodiment, the MIMO detector can first performing a decoding passusing one of the filter based MIMO detectors and if one or more of thecodewords of the multiplexed codewords bitstream is correctly decoded,then the list size for the list based MIMO detectors can be reduced,which allows the codewords that were previously undetected, orimproperly decoded after the first pass to be decoded properly duringthe second pass with the list based detector. Since the list size hasbeen reduced, the complexity of the second pass is also correspondinglyreduced, and throughput of the MIMO receiver can be improved. Thistechnique can be faster than the traditional technique of sendingnegative acknowledgements and receiving retransmissions.

In an embodiment, a filter based MIMO detector, (zero forcing detector,minimum mean-square error detector, decision feedback detector,nulling-canceling detector, or successive interference cancelationdetector) is used to perform a first pass on a set of 4 codewords. Thefirst two decoded codewords pass a parity check (e.g., a cyclicredundancy check) while the second two codewords do not pass. Instead ofsending a NAK immediately back to the transmitter to retransmit, a listbased MIMO detector can perform a second pass and use the filter baseddetector (maximum likelihood detector, maximum a posteriori probabilitydetector, sphere decoding detector, or list sphere decoding detector)output for the first and 2^(nd) codewords in the list size. (i.e.instead of checking all the combinations for the 1^(st) and 2^(nd)codeword, we use the candidate codeword from the filter based detectoroutput). The main reason is since the codewords are already passed thismeans that the filter based output is good enough. Hence these codewordsare used as the candidate codeword in the ML/MAP metric for generatingthe bit likelihood ratios at the list based detector output. i.e thecomplexity of the list based detector is reduced by 2 times as the listsize half of the conventional list based detector algorithm.

Turning now to FIG. 2, illustrated is an example block diagram of amultiple-input multiple output (MIMO) wireless receiver 200 thatfacilitates detecting data in multi-antenna wireless systems inaccordance with various aspects and embodiments of the subjectdisclosure.

A wireless receiver 200 can include Fast Fourier Transform (FFT) blocks202 and 212 that receive transmissions received at respective antennas(Ant 1 to Ant N). The respective transmissions or bitstreams can eachinclude an Orthogonal Frequency Division Multiplexed (OFDM) codewordthat received an N QAM symbol from the MIMO encoder at the transmitter.The transmitter's inverse FFT blocks can convert the N symbols to theOFDM symbols in the time domain, and then the FFT blocks 202 and 212 canconvert the OFDM symbols back to the frequency domain.

A MIMO detector 222 can then perform a first pass with a filter baseddetector to detect/decode one or more of the codewords received from theAnt N antennas, and then demappers 204 and 214 and deinterleavers 206and 216 can then take the respective code words and demap anddeinterleave them. The bitstreams, once deinterleaved can be decoded bydecoders 208 and 218, and if the MIMO detector 222 during the first passcorrectly detected the codewords, CRC components 210 and 220 can performparity checks using CRC bits in the decoded codewords. If the CRCcomponents 210 and 220 determine that one or more of the codewords havebeen correctly decoded, then the interference cancelation block 224 cantake the correctly decoded codewords as candidate codewords, andcalculate bit log-likelihood ratios that can be used as input for asecond pass with the MIMO detector 222 that uses a list based detectionmethod.

The list based detection method can comprise at least one of a maximumlikelihood detector, a maximum a posteriori probability detector, a(ML/MAP) sphere decoding detector, or list sphere decoding detector,which have significantly better bit error rates and frame error ratesthan the filter based detectors, but where the complexity of thedetector increases exponentially with the number of transmit antennasand/or the number of bits per constellation point. By using the input ofthe correctly decoded codewords and bit log-likelihood ratios, the listsize can be reduced for the second pass, and the complexity decreased.MIMO detector 222 can then decode one or more of the rest of thecodewords. If the CRC components 210 and/or 220 determine that there arestill incorrectly decoded codewords, then the process can repeat witheither the filter based detector or list based detector until thecodewords are correctly decoded, or until a certain number of iterationshave passed. If the predefined number of iterations passes, a negativeacknowledgement (NAK) can be sent back to the transmitter to resend thetransmission.

Turning now to FIG. 3, illustrated is an example block diagram 300 of aMIMO bitstream that has two decoding passes performed in accordance withvarious aspects and embodiments of the subject disclosure. Bitstream 302can include a set of multiplexed codewords A 304, B 306, C 308, and D310. Before the first pass 312 with the filter detector, all four greyedout codewords are unknown. After the first pass 312 with the filterdetector (e.g., a zero forcing detector, a minimum mean-square errordetector, a decision feedback detector, a nulling-canceling detector, ora successive interference cancelation detector) codewords A 304 and B306 can be known after a CRC check determines that they were properlydecoded, while codewords C 308 and D 310 remain unknown.

During the second pass with a list based detector (e.g., a maximumlikelihood detector, a maximum a posteriori probability detector, a(MUMAP) sphere decoding detector, or list sphere decoding detector), thelist based detector does not have to go through all the combinations onthe lists for codewords A 304 and B 306 since they are already known.The resulting decrease in complexity can allow the second pass 314 to beperformed more quickly than if the first pass 312 had not beenperformed, and overall throughput can be increased.

Turning now to FIG. 4, illustrated is an example block diagram 400showing a MIMO wireless receiver device 402 in accordance with variousaspects and embodiments of the subject disclosure.

The MIMO wireless receiver device 402 can receive at multiple antennas,a transmission from a MIMO transmitter. The resultant bitstreams can beanalyzed by a MIMO detector 404 to detect one more codewords in thebitstream. The bitstream can comprise a set of multiplexed codewords,wherein the number of multiplexed codewords is based on the number ofantennas. In some embodiments there can be 4 antennas, in others 8antennas, and in yet other 16 or more antennas. The MIMO detector 404can perform a first pass with respect to the bitstream to reduce theinter-stream interference using a first multiple-input multiple-outputdetector. The first detector pass can use a filter based detectiontechniques such as zero forcing, minimum mean-square error, decisionfeedback, nulling-canceling, or successive interference cancelation. Thedecoder 406 can then decode the detected codewords based on theparticular encoding method, and CRC component 408 can check the paritybits of the decoded codewords to see if the codewords weredetected/decoded properly.

If one or more of the codewords were detected/decoded properly, theoutput of the MIMO detector 404 in the first pass can be used as aninput in the second pass, which further reduces the inter-streaminterference. The second pass can use list based detection which cancomprise at least one of a maximum likelihood detector, maximum aposteriori probability detector, sphere decoding detector, or listsphere decoding detector.

If all the codewords are not detected after the second pass, the MIMOdetector 404 can iteratively reperform the first pass and the secondpass until all codewords of the multiplexed codewords are correctlydecoded or until a predefined number of iterations has passed. An ACKcomponent 410 can transmit a negative acknowledgement to a transmitterin response to not decoding all the multiplexed codewords after thepredefined number of iterations has passed. The ACK component 410 canalso transmit an acknowledgement to a transmitter in response todecoding all the multiplexed codewords.

Turning now to FIG. 5, illustrated is an example table 500 showingimprovements to throughput using the MIMO wireless receiver inaccordance with various aspects and embodiments of the subjectdisclosure

Results of improvements can be shown for both configurations 502 ofexemplary embodiments of 2×2 and 4×4 MIMO antennas. Sector throughput504 in Mbps can be compared for just MMSE detectors and the discloseddetector in both 2×2 and 4×4 configurations. Sector throughput using andMMSE is 14.55 Mbps and 20.46 in 2×2 and 4×4 configuration respectively,but using the disclosed detector, the throughput is 18.05 and 26.52respectively.

Cell edge throughput 506 for an MMSE detector is 329 Kbps and 242 Kbpsfor 2×2 and 4×4 antennas respectively, while for the proposed detectorit is 338 Kbps and 375 Kbps respectively.

The percent gain of proposed detector with respect to MMSE in sectorthroughput is 24.05% and 29.62% for 2×2 and 4×4 respectively, while forCell Edge throughput the percent gain is 2.75% and 54.96% respectively.

A graph showing this relationship can be found in FIG. 6 where the MMSELink throughput in Mbps for every dB in SNR is shown by 604, whereas theimprovement is clear for the proposed detector 602, especially in midrange SNR.

FIGS. 7-8 illustrates a process in connection with the aforementionedsystems. The process in FIGS. 7-8 can be implemented for example by thesystems in FIGS. 1-4 respectively. While for purposes of simplicity ofexplanation, the methods are shown and described as a series of blocks,it is to be understood and appreciated that the claimed subject matteris not limited by the order of the blocks, as some blocks may occur indifferent orders and/or concurrently with other blocks from what isdepicted and described herein. Moreover, not all illustrated blocks maybe required to implement the methods described hereinafter.

Turning now to FIG. 7, illustrated is an example method 700 fordetecting data in MIMO wireless receivers in accordance with variousaspects and embodiments of the subject disclosure.

Method 700 can start at 702 where the method comprises receiving, by adevice comprising a processor, a bitstream comprising multiplexedcodewords.

At 704 the method comprises performing, by the device, a first decodingpass with a first multiple-input multiple-output detector.

At 708, the method comprises determining, by the device, that a firstcodeword passes a parity check and a second codeword does not pass theparity check.

At 708, the method comprises performing, by the device, a seconddecoding pass with a second multiple-input multiple-output detector,wherein the first codeword of the first decoding pass is used as acandidate codeword for the second decoding pass.

Turning now to FIG. 8, illustrated is an example method 800 fordetecting data in MIMO wireless receivers in accordance with variousaspects and embodiments of the subject disclosure.

Method 800 can start at 802 where the method comprises receiving abitstream comprising multiplexed codewords, wherein the bitstream issubject to an inter-stream interference.

At 804 the method comprises performing a first pass with respect to thebitstream to reduce the inter-stream interference using a firstmultiple-input multiple-output detector.

At 806, the method comprises determining, by the device, that a firstcodeword passes a parity check and a second codeword does not pass theparity check.

At 808, the method comprises performing a second pass with respect tothe bitstream to further reduce the inter-stream interference using asecond multiple-input multiple-output detector different from the firstmultiple-input multiple-output detector.

Referring now to FIG. 9, illustrated is a schematic block diagram of anexample end-user device such as a user equipment that can be a mobiledevice 900 capable of connecting to a network in accordance with someembodiments described herein. Although a mobile handset 900 isillustrated herein, it will be understood that other devices can be amobile device, and that the mobile handset 900 is merely illustrated toprovide context for the embodiments of the various embodiments describedherein. The following discussion is intended to provide a brief, generaldescription of an example of a suitable environment 900 in which thevarious embodiments can be implemented. While the description comprisesa general context of computer-executable instructions embodied on amachine-readable storage medium, those skilled in the art will recognizethat the innovation also can be implemented in combination with otherprogram modules and/or as a combination of hardware and software.

Generally, applications (e.g., program modules) can comprise routines,programs, components, data structures, etc., that perform particulartasks or implement particular abstract data types. Moreover, thoseskilled in the art will appreciate that the methods described herein canbe practiced with other system configurations, includingsingle-processor or multiprocessor systems, minicomputers, mainframecomputers, as well as personal computers, hand-held computing devices,microprocessor-based or programmable consumer electronics, and the like,each of which can be operatively coupled to one or more associateddevices.

A computing device can typically comprise a variety of machine-readablemedia. Machine-readable media can be any available media that can beaccessed by the computer and comprises both volatile and non-volatilemedia, removable and non-removable media. By way of example and notlimitation, computer-readable media can comprise computer storage mediaand communication media. Computer storage media can comprise volatileand/or non-volatile media, removable and/or non-removable mediaimplemented in any method or technology for storage of information, suchas computer-readable instructions, data structures, program modules orother data. Computer storage media can comprise, but is not limited to,RAM, ROM, EEPROM, flash memory or other memory technology, CD ROM,digital video disk (DVD) or other optical disk storage, magneticcassettes, magnetic tape, magnetic disk storage or other magneticstorage devices, or any other medium which can be used to store thedesired information and which can be accessed by the computer.

Communication media typically embodies computer-readable instructions,data structures, program modules or other data in a modulated datasignal such as a carrier wave or other transport mechanism, andcomprises any information delivery media. The term “modulated datasignal” means a signal that has one or more of its characteristics setor changed in such a manner as to encode information in the signal. Byway of example, and not limitation, communication media comprises wiredmedia such as a wired network or direct-wired connection, and wirelessmedia such as acoustic, RF, infrared and other wireless media.Combinations of the any of the above should also be comprised within thescope of computer-readable media.

The handset 900 comprises a processor 902 for controlling and processingall onboard operations and functions. A memory 904 interfaces to theprocessor 902 for storage of data and one or more applications 906(e.g., a video player software, user feedback component software, etc.).Other applications can comprise voice recognition of predetermined voicecommands that facilitate initiation of the user feedback signals. Theapplications 906 can be stored in the memory 904 and/or in a firmware908, and executed by the processor 902 from either or both the memory904 or/and the firmware 908. The firmware 908 can also store startupcode for execution in initializing the handset 900. A communicationscomponent 910 interfaces to the processor 902 to facilitatewired/wireless communication with external systems, e.g., cellularnetworks, VoIP networks, and so on. Here, the communications component910 can also comprise a suitable cellular transceiver 911 (e.g., a GSMtransceiver) and/or an unlicensed transceiver 913 (e.g., Wi-Fi, WiMax)for corresponding signal communications. The handset 900 can be a devicesuch as a cellular telephone, a PDA with mobile communicationscapabilities, and messaging-centric devices. The communicationscomponent 910 also facilitates communications reception from terrestrialradio networks (e.g., broadcast), digital satellite radio networks, andInternet-based radio services networks.

The handset 900 comprises a display 912 for displaying text, images,video, telephony functions (e.g., a Caller ID function), setupfunctions, and for user input. For example, the display 912 can also bereferred to as a “screen” that can accommodate the presentation ofmultimedia content (e.g., music metadata, messages, wallpaper, graphics,etc.). The display 912 can also display videos and can facilitate thegeneration, editing and sharing of video quotes. A serial I/O interface914 is provided in communication with the processor 902 to facilitatewired and/or wireless serial communications (e.g., USB, and/or IEEE1394) through a hardwire connection, and other serial input devices(e.g., a keyboard, keypad, and mouse). This supports updating andtroubleshooting the handset 900, for example. Audio capabilities areprovided with an audio I/O component 916, which can comprise a speakerfor the output of audio signals related to, for example, indication thatthe user pressed the proper key or key combination to initiate the userfeedback signal. The audio I/O component 916 also facilitates the inputof audio signals through a microphone to record data and/or telephonyvoice data, and for inputting voice signals for telephone conversations.

The handset 900 can comprise a slot interface 918 for accommodating aSIC (Subscriber Identity Component) in the form factor of a cardSubscriber Identity Module (SIM) or universal SIM 920, and interfacingthe SIM card 920 with the processor 902. However, it is to beappreciated that the SIM card 920 can be manufactured into the handset900, and updated by downloading data and software.

The handset 900 can process IP data traffic through the communicationcomponent 910 to accommodate IP traffic from an IP network such as, forexample, the Internet, a corporate intranet, a home network, a personarea network, etc., through an ISP or broadband cable provider. Thus,VoIP traffic can be utilized by the handset 800 and IP-based multimediacontent can be received in either an encoded or decoded format.

A video processing component 922 (e.g., a camera) can be provided fordecoding encoded multimedia content. The video processing component 922can aid in facilitating the generation, editing and sharing of videoquotes. The handset 900 also comprises a power source 924 in the form ofbatteries and/or an AC power subsystem, which power source 924 caninterface to an external power system or charging equipment (not shown)by a power I/O component 926.

The handset 900 can also comprise a video component 930 for processingvideo content received and, for recording and transmitting videocontent. For example, the video component 930 can facilitate thegeneration, editing and sharing of video quotes. A location trackingcomponent 932 facilitates geographically locating the handset 900. Asdescribed hereinabove, this can occur when the user initiates thefeedback signal automatically or manually. A user input component 934facilitates the user initiating the quality feedback signal. The userinput component 934 can also facilitate the generation, editing andsharing of video quotes. The user input component 934 can comprise suchconventional input device technologies such as a keypad, keyboard,mouse, stylus pen, and/or touch screen, for example.

Referring again to the applications 906, a hysteresis component 936facilitates the analysis and processing of hysteresis data, which isutilized to determine when to associate with the access point. Asoftware trigger component 938 can be provided that facilitatestriggering of the hysteresis component 938 when the Wi-Fi transceiver913 detects the beacon of the access point. A SIP client 940 enables thehandset 900 to support SIP protocols and register the subscriber withthe SIP registrar server. The applications 906 can also comprise aclient 942 that provides at least the capability of discovery, play andstore of multimedia content, for example, music.

The handset 900 can comprise an indoor network radio transceiver 913(e.g., Wi-Fi transceiver). This function supports the indoor radio link,such as IEEE 802.11, for the dual-mode GSM handset 900. The handset 900can accommodate at least satellite radio services through a handset thatcan combine wireless voice and digital radio chipsets into a singlehandheld device.

Referring now to FIG. 10, there is illustrated a block diagram of acomputer 1000 operable to execute the functions and operations performedin the described example embodiments. For example, a network node (e.g.,network node 106) may contain components as described in FIG. 10. Thecomputer 1000 can provide networking and communication capabilitiesbetween a wired or wireless communication network and a server and/orcommunication device. In order to provide additional context for variousaspects thereof, FIG. 10 and the following discussion are intended toprovide a brief, general description of a suitable computing environmentin which the various aspects of the innovation can be implemented tofacilitate the establishment of a transaction between an entity and athird party. While the description above is in the general context ofcomputer-executable instructions that can run on one or more computers,those skilled in the art will recognize that the innovation also can beimplemented in combination with other program modules and/or as acombination of hardware and software.

Generally, program modules comprise routines, programs, components, datastructures, etc., that perform particular tasks or implement particularabstract data types. Moreover, those skilled in the art will appreciatethat the inventive methods can be practiced with other computer systemconfigurations, including single-processor or multiprocessor computersystems, minicomputers, mainframe computers, as well as personalcomputers, hand-held computing devices, microprocessor-based orprogrammable consumer electronics, and the like, each of which can beoperatively coupled to one or more associated devices.

The illustrated aspects of the innovation can also be practiced indistributed computing environments where certain tasks are performed byremote processing devices that are linked through a communicationsnetwork. In a distributed computing environment, program modules can belocated in both local and remote memory storage devices.

Computing devices typically comprise a variety of media, which cancomprise computer-readable storage media or communications media, whichtwo terms are used herein differently from one another as follows.

Computer-readable storage media can be any available storage media thatcan be accessed by the computer and comprises both volatile andnonvolatile media, removable and non-removable media. By way of example,and not limitation, computer-readable storage media can be implementedin connection with any method or technology for storage of informationsuch as computer-readable instructions, program modules, structureddata, or unstructured data. Computer-readable storage media cancomprise, but are not limited to, RAM, ROM, EEPROM, flash memory orother memory technology, CD-ROM, digital versatile disk (DVD) or otheroptical disk storage, magnetic cassettes, magnetic tape, magnetic diskstorage or other magnetic storage devices, or other tangible and/ornon-transitory media which can be used to store desired information.Computer-readable storage media can be accessed by one or more local orremote computing devices, e.g., via access requests, queries or otherdata retrieval protocols, for a variety of operations with respect tothe information stored by the medium.

Communications media can embody computer-readable instructions, datastructures, program modules or other structured or unstructured data ina data signal such as a modulated data signal, e.g., a carrier wave orother transport mechanism, and comprises any information delivery ortransport media. The term “modulated data signal” or signals refers to asignal that has one or more of its characteristics set or changed insuch a manner as to encode information in one or more signals. By way ofexample, and not limitation, communication media comprise wired media,such as a wired network or direct-wired connection, and wireless mediasuch as acoustic, RF, infrared and other wireless media.

With reference to FIG. 10, implementing various aspects described hereinwith regards to the end-user device can comprise a computer 1000, thecomputer 1000 including a processing unit 1004, a system memory 1006 anda system bus 1008. The system bus 1008 couples system componentsincluding, but not limited to, the system memory 1006 to the processingunit 1004. The processing unit 1004 can be any of various commerciallyavailable processors. Dual microprocessors and other multi-processorarchitectures can also be employed as the processing unit 1004.

The system bus 1008 can be any of several types of bus structure thatcan further interconnect to a memory bus (with or without a memorycontroller), a peripheral bus, and a local bus using any of a variety ofcommercially available bus architectures. The system memory 1006comprises read-only memory (ROM) 1027 and random access memory (RAM)1012. A basic input/output system (BIOS) is stored in a non-volatilememory 1027 such as ROM, EPROM, EEPROM, which BIOS contains the basicroutines that help to transfer information between elements within thecomputer 1000, such as during start-up. The RAM 1012 can also comprise ahigh-speed RAM such as static RAM for caching data.

The computer 1000 further comprises an internal hard disk drive (HDD)1014 (e.g., EIDE, SATA), which internal hard disk drive 1014 can also beconfigured for external use in a suitable chassis (not shown), amagnetic floppy disk drive (FDD) 1016, (e.g., to read from or write to aremovable diskette 1018) and an optical disk drive 1020, (e.g., readinga CD-ROM disk 1022 or, to read from or write to other high capacityoptical media such as the DVD). The hard disk drive 1014, magnetic diskdrive 1016 and optical disk drive 1020 can be connected to the systembus 1008 by a hard disk drive interface 1024, a magnetic disk driveinterface 1026 and an optical drive interface 1028, respectively. Theinterface 1024 for external drive implementations comprises at least oneor both of Universal Serial Bus (USB) and IEEE 1394 interfacetechnologies. Other external drive connection technologies are withincontemplation of the subject innovation.

The drives and their associated computer-readable media providenonvolatile storage of data, data structures, computer-executableinstructions, and so forth. For the computer 1000 the drives and mediaaccommodate the storage of any data in a suitable digital format.Although the description of computer-readable media above refers to aHDD, a removable magnetic diskette, and a removable optical media suchas a CD or DVD, it should be appreciated by those skilled in the artthat other types of media which are readable by a computer 1000, such aszip drives, magnetic cassettes, flash memory cards, cartridges, and thelike, can also be used in the example operating environment, andfurther, that any such media can contain computer-executableinstructions for performing the methods of the disclosed innovation.

A number of program modules can be stored in the drives and RAM 1012,including an operating system 1030, one or more application programs1032, other program modules 1034 and program data 1036. All or portionsof the operating system, applications, modules, and/or data can also becached in the RAM 1012. It is to be appreciated that the innovation canbe implemented with various commercially available operating systems orcombinations of operating systems.

A user can enter commands and information into the computer 1000 throughone or more wired/wireless input devices, e.g., a keyboard 1038 and apointing device, such as a mouse 1040. Other input devices (not shown)may comprise a microphone, an IR remote control, a joystick, a game pad,a stylus pen, touch screen, or the like. These and other input devicesare often connected to the processing unit 1004 through an input deviceinterface 1042 that is coupled to the system bus 1008, but can beconnected by other interfaces, such as a parallel port, an IEEE 1394serial port, a game port, a USB port, an IR interface, etc.

A monitor 1044 or other type of display device is also connected to thesystem bus 1008 through an interface, such as a video adapter 1046. Inaddition to the monitor 1044, a computer 1000 typically comprises otherperipheral output devices (not shown), such as speakers, printers, etc.

The computer 1000 can operate in a networked environment using logicalconnections by wired and/or wireless communications to one or moreremote computers, such as a remote computer(s) 1048. The remotecomputer(s) 1048 can be a workstation, a server computer, a router, apersonal computer, portable computer, microprocessor-based entertainmentdevice, a peer device or other common network node, and typicallycomprises many or all of the elements described relative to thecomputer, although, for purposes of brevity, only a memory/storagedevice 1050 is illustrated. The logical connections depicted comprisewired/wireless connectivity to a local area network (LAN) 1052 and/orlarger networks, e.g., a wide area network (WAN) 1054. Such LAN and WANnetworking environments are commonplace in offices and companies, andfacilitate enterprise-wide computer networks, such as intranets, all ofwhich may connect to a global communications network, e.g., theInternet.

When used in a LAN networking environment, the computer 1000 isconnected to the local network 1052 through a wired and/or wirelesscommunication network interface or adapter 1056. The adapter 1056 mayfacilitate wired or wireless communication to the LAN 1052, which mayalso comprise a wireless access point disposed thereon for communicatingwith the wireless adapter 1056.

When used in a WAN networking environment, the computer 1000 cancomprise a modem 1058, or is connected to a communications server on theWAN 1054, or has other means for establishing communications over theWAN 1054, such as by way of the Internet. The modem 1058, which can beinternal or external and a wired or wireless device, is connected to thesystem bus 1008 through the input device interface 1042. In a networkedenvironment, program modules depicted relative to the computer, orportions thereof, can be stored in the remote memory/storage device1050. It will be appreciated that the network connections shown areexemplary and other means of establishing a communications link betweenthe computers can be used.

The computer is operable to communicate with any wireless devices orentities operatively disposed in wireless communication, e.g., aprinter, scanner, desktop and/or portable computer, portable dataassistant, communications satellite, any piece of equipment or locationassociated with a wirelessly detectable tag (e.g., a kiosk, news stand,restroom), and telephone. This comprises at least Wi-Fi and Bluetooth™wireless technologies. Thus, the communication can be a predefinedstructure as with a conventional network or simply an ad hoccommunication between at least two devices.

Wi-Fi, or Wireless Fidelity, allows connection to the Internet from acouch at home, a bed in a hotel room, or a conference room at work,without wires. Wi-Fi is a wireless technology similar to that used in acell phone that enables such devices, e.g., computers, to send andreceive data indoors and out; anywhere within the range of a basestation. Wi-Fi networks use radio technologies called IEEE802.11 (a, b,g, n, etc.) to provide secure, reliable, fast wireless connectivity. AWi-Fi network can be used to connect computers to each other, to theInternet, and to wired networks (which use IEEE802.3 or Ethernet). Wi-Finetworks operate in the unlicensed 2.4 and 5 GHz radio bands, at an 11Mbps (802.11b) or 54 Mbps (802.11a) data rate, for example, or withproducts that contain both bands (dual band), so the networks canprovide real-world performance similar to the basic “10BaseT” wiredEthernet networks used in many offices.

As used in this application, the terms “system,” “component,”“interface,” and the like are generally intended to refer to acomputer-related entity or an entity related to an operational machinewith one or more specific functionalities. The entities disclosed hereincan be either hardware, a combination of hardware and software,software, or software in execution. For example, a component may be, butis not limited to being, a process running on a processor, a processor,an object, an executable, a thread of execution, a program, and/or acomputer. By way of illustration, both an application running on aserver and the server can be a component. One or more components mayreside within a process and/or thread of execution and a component maybe localized on one computer and/or distributed between two or morecomputers. These components also can execute from various computerreadable storage media having various data structures stored thereon.The components may communicate via local and/or remote processes such asin accordance with a signal having one or more data packets (e.g., datafrom one component interacting with another component in a local system,distributed system, and/or across a network such as the Internet withother systems via the signal). As another example, a component can be anapparatus with specific functionality provided by mechanical partsoperated by electric or electronic circuitry that is operated bysoftware or firmware application(s) executed by a processor, wherein theprocessor can be internal or external to the apparatus and executes atleast a part of the software or firmware application. As yet anotherexample, a component can be an apparatus that provides specificfunctionality through electronic components without mechanical parts,the electronic components can comprise a processor therein to executesoftware or firmware that confers at least in part the functionality ofthe electronic components. An interface can comprise input/output (I/O)components as well as associated processor, application, and/or APIcomponents.

Furthermore, the disclosed subject matter may be implemented as amethod, apparatus, or article of manufacture using standard programmingand/or engineering techniques to produce software, firmware, hardware,or any combination thereof to control a computer to implement thedisclosed subject matter. The term “article of manufacture” as usedherein is intended to encompass a computer program accessible from anycomputer-readable device, computer-readable carrier, orcomputer-readable media. For example, computer-readable media cancomprise, but are not limited to, a magnetic storage device, e.g., harddisk; floppy disk; magnetic strip(s); an optical disk (e.g., compactdisk (CD), a digital video disc (DVD), a Blu-ray Disc™ (BD)); a smartcard; a flash memory device (e.g., card, stick, key drive); and/or avirtual device that emulates a storage device and/or any of the abovecomputer-readable media.

As it employed in the subject specification, the term “processor” canrefer to substantially any computing processing unit or devicecomprising, but not limited to comprising, single-core processors;single-processors with software multithread execution capability;multi-core processors; multi-core processors with software multithreadexecution capability; multi-core processors with hardware multithreadtechnology; parallel platforms; and parallel platforms with distributedshared memory. Additionally, a processor can refer to an integratedcircuit, an application specific integrated circuit (ASIC), a digitalsignal processor (DSP), a field programmable gate array (FPGA), aprogrammable logic controller (PLC), a complex programmable logic device(CPLD), a discrete gate or transistor logic, discrete hardwarecomponents, or any combination thereof designed to perform the functionsdescribed herein. Processors can exploit nano-scale architectures suchas, but not limited to, molecular and quantum-dot based transistors,switches and gates, in order to optimize space usage or enhanceperformance of user equipment. A processor also can be implemented as acombination of computing processing units.

In the subject specification, terms such as “store,” “data store,” “datastorage,” “database,” “repository,” “queue”, and substantially any otherinformation storage component relevant to operation and functionality ofa component, refer to “memory components,” or entities embodied in a“memory” or components comprising the memory. It will be appreciatedthat the memory components described herein can be either volatilememory or nonvolatile memory, or can comprise both volatile andnonvolatile memory. In addition, memory components or memory elementscan be removable or stationary. Moreover, memory can be internal orexternal to a device or component, or removable or stationary. Memorycan comprise various types of media that are readable by a computer,such as hard-disc drives, zip drives, magnetic cassettes, flash memorycards or other types of memory cards, cartridges, or the like.

By way of illustration, and not limitation, nonvolatile memory cancomprise read only memory (ROM), programmable ROM (PROM), electricallyprogrammable ROM (EPROM), electrically erasable ROM (EEPROM), or flashmemory. Volatile memory can comprise random access memory (RAM), whichacts as external cache memory. By way of illustration and notlimitation, RAM is available in many forms such as synchronous RAM(SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rateSDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), Synchlink DRAM (SLDRAM), anddirect Rambus RAM (DRRAM). Additionally, the disclosed memory componentsof systems or methods herein are intended to comprise, without beinglimited to comprising, these and any other suitable types of memory.

In particular and in regard to the various functions performed by theabove described components, devices, circuits, systems and the like, theterms (including a reference to a “means”) used to describe suchcomponents are intended to correspond, unless otherwise indicated, toany component which performs the specified function of the describedcomponent (e.g., a functional equivalent), even though not structurallyequivalent to the disclosed structure, which performs the function inthe herein illustrated example aspects of the embodiments. In thisregard, it will also be recognized that the embodiments comprises asystem as well as a computer-readable medium having computer-executableinstructions for performing the acts and/or events of the variousmethods.

Computing devices typically comprise a variety of media, which cancomprise computer-readable storage media and/or communications media,which two terms are used herein differently from one another as follows.Computer-readable storage media can be any available storage media thatcan be accessed by the computer and comprises both volatile andnonvolatile media, removable and non-removable media. By way of example,and not limitation, computer-readable storage media can be implementedin connection with any method or technology for storage of informationsuch as computer-readable instructions, program modules, structureddata, or unstructured data. Computer-readable storage media cancomprise, but are not limited to, RAM, ROM, EEPROM, flash memory orother memory technology, CD-ROM, digital versatile disk (DVD) or otheroptical disk storage, magnetic cassettes, magnetic tape, magnetic diskstorage or other magnetic storage devices, or other tangible and/ornon-transitory media which can be used to store desired information.Computer-readable storage media can be accessed by one or more local orremote computing devices, e.g., via access requests, queries or otherdata retrieval protocols, for a variety of operations with respect tothe information stored by the medium.

On the other hand, communications media typically embodycomputer-readable instructions, data structures, program modules orother structured or unstructured data in a data signal such as amodulated data signal, e.g., a carrier wave or other transportmechanism, and comprises any information delivery or transport media.The term “modulated data signal” or signals refers to a signal that hasone or more of its characteristics set or changed in such a manner as toencode information in one or more signals. By way of example, and notlimitation, communications media comprise wired media, such as a wirednetwork or direct-wired connection, and wireless media such as acoustic,RF, infrared and other wireless media

Further, terms like “user equipment,” “user device,” “mobile device,”“mobile,” station,” “access terminal,” “terminal,” “handset,” andsimilar terminology, generally refer to a wireless device utilized by asubscriber or user of a wireless communication network or service toreceive or convey data, control, voice, video, sound, gaming, orsubstantially any data-stream or signaling-stream. The foregoing termsare utilized interchangeably in the subject specification and relateddrawings. Likewise, the terms “access point,” “node B,” “base station,”“evolved Node B,” “cell,” “cell site,” and the like, can be utilizedinterchangeably in the subject application, and refer to a wirelessnetwork component or appliance that serves and receives data, control,voice, video, sound, gaming, or substantially any data-stream orsignaling-stream from a set of subscriber stations. Data and signalingstreams can be packetized or frame-based flows. It is noted that in thesubject specification and drawings, context or explicit distinctionprovides differentiation with respect to access points or base stationsthat serve and receive data from a mobile device in an outdoorenvironment, and access points or base stations that operate in aconfined, primarily indoor environment overlaid in an outdoor coveragearea. Data and signaling streams can be packetized or frame-based flows.

Furthermore, the terms “user,” “subscriber,” “customer,” “consumer,” andthe like are employed interchangeably throughout the subjectspecification, unless context warrants particular distinction(s) amongthe terms. It should be appreciated that such terms can refer to humanentities, associated devices, or automated components supported throughartificial intelligence (e.g., a capacity to make inference based oncomplex mathematical formalisms) which can provide simulated vision,sound recognition and so forth. In addition, the terms “wirelessnetwork” and “network” are used interchangeable in the subjectapplication, when context wherein the term is utilized warrantsdistinction for clarity purposes such distinction is made explicit.

Moreover, the word “exemplary” is used herein to mean serving as anexample, instance, or illustration. Any aspect or design describedherein as “exemplary” is not necessarily to be construed as preferred oradvantageous over other aspects or designs. Rather, use of the wordexemplary is intended to present concepts in a concrete fashion. As usedin this application, the term “or” is intended to mean an inclusive “or”rather than an exclusive “or”. That is, unless specified otherwise, orclear from context, “X employs A or B” is intended to mean any of thenatural inclusive permutations. That is, if X employs A; X employs B; orX employs both A and B, then “X employs A or B” is satisfied under anyof the foregoing instances. In addition, the articles “a” and “an” asused in this application and the appended claims should generally beconstrued to mean “one or more” unless specified otherwise or clear fromcontext to be directed to a singular form.

In addition, while a particular feature may have been disclosed withrespect to only one of several implementations, such feature may becombined with one or more other features of the other implementations asmay be desired and advantageous for any given or particular application.Furthermore, to the extent that the terms “comprises” and “including”and variants thereof are used in either the detailed description or theclaims, these terms are intended to be inclusive in a manner similar tothe term “comprising.”

The above descriptions of various embodiments of the subject disclosureand corresponding figures and what is described in the Abstract, aredescribed herein for illustrative purposes, and are not intended to beexhaustive or to limit the disclosed embodiments to the precise formsdisclosed. It is to be understood that one of ordinary skill in the artmay recognize that other embodiments having modifications, permutations,combinations, and additions can be implemented for performing the same,similar, alternative, or substitute functions of the disclosed subjectmatter, and are therefore considered within the scope of thisdisclosure. Therefore, the disclosed subject matter should not belimited to any single embodiment described herein, but rather should beconstrued in breadth and scope in accordance with the claims below.

What is claimed is:
 1. A system, comprising: a processor; and a memorythat stores executable instructions that, when executed by theprocessor, facilitate performance of operations, comprising: receiving abitstream comprising multiplexed codewords, wherein the bitstream issubject to an inter-stream interference; performing a first pass withrespect to the bitstream to reduce the inter-stream interference using afirst multiple-input multiple-output detector; in response to performingthe first pass, determining that a first codeword of the multiplexedcodewords passed a parity check and a second codeword of the multiplexedcodewords did not pass the parity check; generating a bit log-likelihoodratio based on the first codeword, wherein the first codeword is acandidate codeword; and performing a second pass with respect to thebitstream to further reduce the inter-stream interference using a secondmultiple-input multiple-output detector different from the firstmultiple-input multiple-output detector, wherein the bit log-likelihoodratio is used as an input for the second pass to reduce a data structuresize associated with the second pass.
 2. The system of claim 1, whereinthe first multiple-input multiple-output detector uses filter baseddetection, and wherein the second multiple-input multiple-outputdetector uses list based detection.
 3. The system of claim 2, whereinthe first multiple-input multiple-output detector is at least one of azero forcing detector, a minimum mean-square error detector, a decisionfeedback detector, a nulling-canceling detector, or a successiveinterference cancelation detector.
 4. The system of claim 2, wherein thesecond multiple-input multiple-output detector is at least one of amaximum likelihood detector, a maximum a posteriori probabilitydetector, a sphere decoding detector, or a list sphere decodingdetector.
 5. The system of claim 1, wherein a first list size associatedwith the first pass is larger than a second list size associated withthe second pass.
 6. The system of claim 1, wherein the operationsfurther comprise: iteratively performing the first pass and the secondpass until all codewords of the multiplexed codewords are correctlydecoded.
 7. The system of claim 1, wherein the operations furthercomprise: transmitting a negative acknowledgement to a transmitter inresponse to not having decoded all the multiplexed codewords after apredefined number of iterations has passed.
 8. The system of claim 1,wherein the operations further comprise: transmitting an acknowledgementto a transmitter in response to having decoded all the multiplexedcodewords.
 9. A method, comprising: receiving, by a device comprising aprocessor, a bitstream comprising multiplexed codewords; performing, bythe device, a first decoding pass with a first multiple-inputmultiple-output detector; determining, by the device, that a firstcodeword passes a parity check and a second codeword does not pass theparity check; generating, by the device, a bit log-likelihood ratiobased on the first codeword which is used as a candidate codeword; andperforming, by the device, a second decoding pass with a secondmultiple-input multiple-output detector, wherein the bit log-likelihoodratio is used as an input for the second decoding pass to reduce a datastructure size associated with the second pass.
 10. The method of claim9, wherein the candidate codeword reduces a list size of the seconddecoding pass relative to the first decoding pass.
 11. The method ofclaim 9, wherein the first multiple-input multiple-output detector usesfilter based detection, and wherein the second multiple-inputmultiple-output detector uses list based detection.
 12. The method ofclaim 9, further comprising: performing, by the device, iterations ofthe first decoding pass and the second decoding pass until a predefinednumber of iterations has passed.
 13. The method of claim 12, furthercomprising: transmitting, by the device, a negative acknowledgement to atransmitter in response to not decoding all the multiplexed codewordsafter the predefined number of iterations has passed.
 14. Anon-transitory machine-readable storage medium, comprising executableinstructions that, when executed by a processor of a device, facilitateperformance of operations, comprising: receiving a signal from amultiple-input multiple-output antenna, the signal comprisingmultiplexed codewords; performing a first decoding pass on themultiplexed codewords with a first multiple-input multiple-outputdetector; determining that a first codeword of the multiplexed codewordspasses a parity check and a second codeword of the multiplexed codewordsdoes not pass the parity check; generating a bit log-likelihood ratiofrom an output of the first decoding pass; and performing a seconddecoding pass with a second multiple-input multiple-output detector todecode the second codeword, wherein the bit log-likelihood ratio is usedas an input for the second decoding pass to reduce a data structure sizeassociated with the second decoding pass.
 15. The non-transitorymachine-readable storage medium of claim 14, wherein the generating thebit log-likelihood ratio further comprises generating the bitlog-likelihood ratio based on the first codeword.
 16. The non-transitorymachine-readable storage medium of claim 14, wherein the operationsfurther comprise: performing a predefined number of iterations of thefirst decoding pass and the second decoding pass until all codewords ofthe multiplexed codewords are correctly decoded or until a predefinednumber of iterations has passed.
 17. The non-transitory machine-readablestorage medium of claim 14, wherein the first multiple-inputmultiple-output detector uses filter based detection, and wherein thesecond multiple-input multiple-output detector uses list baseddetection.
 18. The non-transitory machine-readable storage medium ofclaim 14, wherein the first multiple-input multiple-output detector isat least one of a zero forcing detector, a minimum mean-square errordetector, a decision feedback detector, a nulling-canceling detector, ora successive interference cancelation detector, and wherein the secondmultiple-input multiple-output detector is at least one of a maximumlikelihood detector, a maximum a posteriori probability detector, asphere decoding detector, or a list sphere decoding detector.
 19. Thenon-transitory machine-readable storage medium of claim 14, wherein theoperations further comprise: iteratively performing the first decodingpass and the second decoding pass until all codewords of the multiplexedcodewords are correctly decoded.
 20. The non-transitory machine-readablestorage medium of claim 19, wherein the operations further comprise:transmitting a negative acknowledgement to a transmitter of the signalin response to not having decoded all the multiplexed codewords after apredefined number of iterations has passed.